1. Biodiversity: At Risk and The Future
Unit 4: The Biosphere

2. Mass Extinctions The last ones was 65 million years ago
Rate of extinction has increased 50x since 1800; by % of all species on earth since then
Those at risk:
Small populations
Migratory populations
That need large an/or specialized
habitats
Exploited by humans
Takes millions of years to rebound

3. To what Extent Do Humans Play a Role?
Habitat Loss/Fragmentation (review)
Invasive species – an introduced species not native to a particular region
Compete for resources; prey on organisms that have no defense
Excessive harvesting, hunting, and poaching (illegal)
Pollution – pesticides (DDT), cleaning agents, drugs, etc. are making their way into ecosystems
Florida Panther – population was down to 100 individuals in 2003!
Was actually onced used in traditional Chinese medicine, but today more a symbol for wealth and status

5. Areas of Critical Biodiversity
All of these areas have a large number of endemic species (only found there)
Rain forests – many unknown species as well!
Coral reefs – majority of biodiversity in the ocean; why?
Islands – Australia! (name one)
Three biodiversity hotspots in the U.S.
California Floristic Province, The Everglades, and Hawaii
3500 plant species; 2000 of which are endemic, and 600 of which are threatened or endangered!

7. So What Are We Doing About It?
Last resorts:
Captive-breeding programs
Gene banks
Zoos, aquariums, parks, and
gardens (botanical)
Protecting and rebuilding
ecosystems/habitats over species
Wetland banking
Legislation – power of the individual!
U.S. Endangered Species Act, CITES treaty, Earth Summit, private efforts ($$$)

8. Concept Mapping
Aka how to study for a test!